It mostly seemed odd to say/imply "My employer treats me like an adult" about permissive WFH, but then turn around and assume that sick days must be carefully tracked. And it seemed like a number of people were talking past each other based on having opposite assumptions about both of these.
Should they? Yes.
However, by your definition the vast, vast majority of employers do not treat their employees like adults. Even those in this industry, which seems to be the only one to adopt "take as you need" sick and vacation time in any significant way.
This is mostly a reaction to the incredulity I (perhaps mis-)read in your statement.